2-吡啶基咪唑并[1,2-a]吡啶的水中合成

2-乙酰基吡啶1经溴化反应后得到2-(2-溴乙酰基)吡啶氢溴酸盐2,2在水中与NaHCO3发生中和反应生成2-(2-溴乙酰基)吡啶,不经分离直接于水中和2-氨基吡啶衍生物3a-3h反应生成2-吡啶基咪唑并1,2-a]吡啶4a-4h.采用核磁共振谱仪、红外光谱仪及质谱仪表征了产物的结构.结果表明,利用该方法可以在温和的反应条件下高产率得到目标产物,且方法操作简便、对环境友好.

Synthesis of 2-pyridylimidazo[1,2-a] pyridine in water

2-acetylpyridine,1,was allowed to take part in bromination reaction generating 2-（2-bromoacetyl） pyridine hydrobromide 2.Compound 2 was neutralized by NaHCO3 in water to give 2-（bromoacetyl） pyridine.Without separation,2-（bromoacetyl） pyridine reacted with the derivatives of 2-aminopyridine 3a-3h directly in water to give 2-pyridylimidazo pyridine 4a-4h successfully.The structures of as-synthesized compounds 4a-4h were characterized by nuclear magnetic resonance spectroscopy,infrared spectrometry,and mass spectrometry.Results indicate that the present route can be readily adopted to synthesize title compounds in high yields under mild reaction conditions,and the route has the advantages of simple protocol and environmental friendliness.